Bouchard's win set up a potential quarterfinal clash against Sharapova, who beat her in the semifinals en route to the French Open crown last month. No. 5 Sharapova had her fourth-round match against No. 9 seed Angelique Kerber of Germany postponed by bad weather to today.

"We had a tough match recently at the French Open," Bouchard said of Sharapova. "But that's the past."

In a season when big names have stumbled and upstarts have struggled to maintain consistency, Bouchard has been big-match bedrock.

The 20-year-old Montreal native broke through at the Australian Open by reaching the semifinals and backed it up by reaching the last four at the French Open. She is the only WTA player to reach that stage in both majors this year.

Bouchard, who was ranked No. 66 a year ago, is single-minded, intense and fears no one. She rarely falters when behind. She is competent on all surfaces.

Bouchard trailed 5-3 in the second set against Cornet, who upset No. 1 Serena Williams, but rallied to win the last four games.

"On the court I really try to have, like, blinders on and really focus throughout the whole match," Bouchard said.

She isn't averse to showing personality. After her third-round match, Bouchard performed her media duties dressed in a red kimono – a gift from a Japanese TV crew.

She joked about her "princess" tendencies, such as being moody in the morning and letting her fitness trainer carry her racket bags.

She cheekily called her mother, who was in the media room, a "closet Royalist" for naming her four children (with Beatrice, Charlotte and William) after British royalty.

"Life is short," Bouchard said, "so have fun."

TV actor Jim Parsons has been to every match of Eugenie Bouchard at Wimbledon this year.(Photo: Susan Mullane, USA TODAY Sports)

She isn't shy about professing her affection for fellow Canuck Justin Bieber and shares a mutual admiration for The Big Bang Theory star Jim Parsons, who has been attending her matches at Wimbledon and emails her after every one.

There is nothing funny about her ambition.

"I don't think the tennis tour is the place to have friends," Bouchard said in Paris. "For me it's all competition."

In just her second full year on tour, the 2012 Wimbledon junior champion won her first title in May, at Nurnberg, Germany, and has advanced to the quarterfinals or better in half the six Grand Slam events she has entered.

"She'd walk in the door and be doing her homework five minutes later, whereas the others were looking for the food and the television," Leclair said.

"It's a double-edged sword," she said of her daughter's rapid success. "She's handling it well, that's the most important thing."

Although not physically imposing, the 5-10 Bouchard cuts off time on plays by taking the ball early, defends well and is adept coming into net.

But her coach, Nick Saviano, says Bouchard's best qualities are her relentless desire to improve and innate poise.

"Genie is always comfortable on a big stage," said Saviano, who has known Bouchard since she was 12 and working at his Florida academy. "Always has been. It's something you could say she was born with."

LONDON, ENGLAND - JUNE 30: Freya Christie of Great Britain during her Girls' Singles first round match against Marketa Vondrousova of Czech Republic on day seven of the Wimbledon Lawn Tennis Championships at the All England Lawn Tennis and Croquet Club on June 30, 2014 in London, England. (Photo by Matthew Stockman/Getty Images) ORG XMIT: 493862681 ORIG FILE ID: 451499076 Matthew Stockman Getty Images

LONDON, ENGLAND - JUNE 30: General view of Tennis balls on the grass on day seven of the Wimbledon Lawn Tennis Championships at the All England Lawn Tennis and Croquet Club on June 30, 2014 in London, England. (Photo by Clive Brunskill/Getty Images) ORG XMIT: 493862681 ORIG FILE ID: 451498972 Clive Brunskill Getty Images